Top band or one hundred and sixty metres is a difficult band when it comes to aerials, a half wave dipole is 264 Feet long and it needs to be well up in clear sky to operate correctly, no mean task for many radio hams and Short Wave listeners alike. A full wave loop is larger and only possible for the Radio Amateur with a lot of real space; however my results have been successful, using a loaded vertical for top band. Read further to discover how I managed to get a signal on 1.850 Megahertz from North East England to New Found land.

The aerial I am going to describe is a loaded dipole; loading usually refers to a coil placed at the bottom of an aerial or in the middle, where it radiated the signal better. Top hat loaded requires a number of radial wires placed on the top of the radiator, these work extremely well, however read on to see how I achieved a DX or long distant contact on top band.

You need two lengths of 140 Feet of wire to construct the aerial one is used as a radiating element, 70 Feet of this length is carefully wound around a length of strong plastic pipe, the remaining 70 foot is either sloped down into a back garden from a mast on the side of the house, or if ground mounted, tethered up to a pole mounted on the side of your house. My experiments with both methods and can conclude that the first method is best because the loading coil is above ground allowing current to radiate more efficiently. Weather proof where you have soldered the coaxial cable to the radiating elements, use self amalgamating tape or duct tape, both work and keep out the water from your coaxial cable.

If you're loaded dipole is mounted on a pole as high as you can get it above ground level, the end of the wire is then connected to the inner of a length of 50 ohm coaxial cable. You probably realise that this is only one part of the aerial. You now need to run a radial wire to complete the circuit. Your radial wire is soldered to the braid of your coaxial cable, cut to 140 Feet the wire is dropped down from the loaded vertical aerial.

Stapling this radial wire to the wall and down the side of my garage; some pruning is needed here to achieve resonance. If your space permits more radial wires I would certainly add two more, adding radial wires will match your aerial and make it more efficient in radiating your signal. With one hundred watts and favourable conditions DX or long distance stations can be worked. A top band contest or another 160 metre activity day for example a field day contest will further prove your aerial.

Top band is primarily a Night Time band; The reflective layers above our heads do not permit day time contacts over long distances; however a few miles across town are well within your reach. The Q of this aerial is very high and do not expect a wide bandwidth, tuning 5 to 7 kilohertz either side of the resonant frequency will alter the S.W.R.(Standing Wave Ratio), reading. My interest on 160 metres is mainly long distance, tuned to 1.850 Megahertz is where most of the DX operates. A matching unit to alter the impedance will allow the entire band to be utilised. Good luck with you 160 metre experiments.

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